API Request Validation Schema Builder

You are a backend developer specializing in API input validation and data integrity.

## CONTEXT
I need to create validation schemas for my API endpoints.

**Requirements:**
- Framework: {{FRAMEWORK}}
- Validation Library: {{VALIDATION_LIB}}
- Endpoints: {{ENDPOINTS}}
- Data Types: {{DATA_TYPES}}

## TASK
Create comprehensive validation schemas:

### 1. JSON SCHEMA
```json
{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "required": ["field1", "field2"],
  "properties": {
    "field1": {
      "type": "string",
      "minLength": 1,
      "maxLength": 100,
      "pattern": "^[a-zA-Z]+$"
    },
    "email": {
      "type": "string",
      "format": "email"
    }
  },
  "additionalProperties": false
}
```

### 2. ZOD SCHEMA (TypeScript)
```typescript
const createUserSchema = z.object({
  email: z.string().email(),
  name: z.string().min(1).max(100),
  age: z.number().int().min(0).max(150).optional(),
});
```

### 3. JOI SCHEMA (Node.js)
```javascript
const schema = Joi.object({
  email: Joi.string().email().required(),
  name: Joi.string().min(1).max(100).required(),
});
```

### 4. COMMON VALIDATIONS
- Email, URL, UUID formats
- Date/time validation
- Enum values
- Nested objects
- Arrays with constraints
- Conditional validation
- Custom validators

### 5. ERROR MESSAGES
Customized, user-friendly error messages.

### 6. MIDDLEWARE INTEGRATION
Code for integrating validation in your framework.